mountmgr: Add some helpers to abstract the Unix calls from device.c.

dlls/mountmgr.sys/Makefile.in

@@ -10,4 +10,5 @@ C_SRCS = \
 	dbus.c \
 	device.c \
 	diskarb.c \
-	mountmgr.c
+	mountmgr.c \
+	unixlib.c

dlls/mountmgr.sys/unixlib.c

+/*
+ * MountMgr Unix interface
+ *
+ * Copyright 2021 Alexandre Julliard
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#include "config.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "unixlib.h"
+
+
+static char *get_dosdevices_path( const char *dev )
+{
+    const char *home = getenv( "HOME" );
+    const char *prefix = getenv( "WINEPREFIX" );
+    size_t len = (prefix ? strlen(prefix) : strlen(home) + strlen("/.wine")) + sizeof("/dosdevices/") + strlen(dev);
+    char *path = malloc( len );
+
+    if (path)
+    {
+        if (prefix) strcpy( path, prefix );
+        else
+        {
+            strcpy( path, home );
+            strcat( path, "/.wine" );
+        }
+        strcat( path, "/dosdevices/" );
+        strcat( path, dev );
+    }
+    return path;
+}
+
+static BOOL is_valid_device( struct stat *st )
+{
+#if defined(linux) || defined(__sun__)
+    return S_ISBLK( st->st_mode );
+#else
+    /* disks are char devices on *BSD */
+    return S_ISCHR( st->st_mode );
+#endif
+}
+
+static void detect_devices( const char **paths, char *names, ULONG size )
+{
+    while (*paths)
+    {
+        char unix_path[32];
+        unsigned int i = 0;
+
+        for (;;)
+        {
+            int len = sprintf( unix_path, *paths, i++ );
+            if (len + 2 > size) break;
+            if (access( unix_path, F_OK ) != 0) break;
+            strcpy( names, unix_path );
+            names += len + 1;
+            size -= len + 1;
+        }
+        paths++;
+    }
+    *names = 0;
+}
+
+/* find or create a DOS drive for the corresponding Unix device */
+NTSTATUS add_drive( const char *device, enum device_type type, int *letter )
+{
+    char *path, *p;
+    char in_use[26];
+    struct stat dev_st, drive_st;
+    int drive, first, last, avail = 0;
+
+    if (stat( device, &dev_st ) == -1 || !is_valid_device( &dev_st )) return STATUS_NO_SUCH_DEVICE;
+
+    if (!(path = get_dosdevices_path( "a::" ))) return STATUS_NO_MEMORY;
+    p = path + strlen(path) - 3;
+
+    memset( in_use, 0, sizeof(in_use) );
+
+    switch (type)
+    {
+    case DEVICE_FLOPPY:
+        first = 0;
+        last = 2;
+        break;
+    case DEVICE_CDROM:
+    case DEVICE_DVD:
+        first = 3;
+        last = 26;
+        break;
+    default:
+        first = 2;
+        last = 26;
+        break;
+    }
+
+    while (avail != -1)
+    {
+        avail = -1;
+        for (drive = first; drive < last; drive++)
+        {
+            if (in_use[drive]) continue;  /* already checked */
+            *p = 'a' + drive;
+            if (stat( path, &drive_st ) == -1)
+            {
+                if (lstat( path, &drive_st ) == -1 && errno == ENOENT)  /* this is a candidate */
+                {
+                    if (avail == -1)
+                    {
+                        p[2] = 0;
+                        /* if mount point symlink doesn't exist either, it's available */
+                        if (lstat( path, &drive_st ) == -1 && errno == ENOENT) avail = drive;
+                        p[2] = ':';
+                    }
+                }
+                else in_use[drive] = 1;
+            }
+            else
+            {
+                in_use[drive] = 1;
+                if (!is_valid_device( &drive_st )) continue;
+                if (dev_st.st_rdev == drive_st.st_rdev) goto done;
+            }
+        }
+        if (avail != -1)
+        {
+            /* try to use the one we found */
+            drive = avail;
+            *p = 'a' + drive;
+            if (symlink( device, path ) != -1) goto done;
+            /* failed, retry the search */
+        }
+    }
+    free( path );
+    return STATUS_OBJECT_NAME_COLLISION;
+
+done:
+    free( path );
+    *letter = drive;
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS get_dosdev_symlink( const char *dev, char *buffer, ULONG size )
+{
+    char *path;
+    int ret;
+
+    if (!(path = get_dosdevices_path( dev ))) return STATUS_NO_MEMORY;
+
+    ret = readlink( path, buffer, size );
+    free( path );
+    if (ret == -1) return STATUS_NO_SUCH_DEVICE;
+    if (ret == size) return STATUS_BUFFER_TOO_SMALL;
+    buffer[ret] = 0;
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS set_dosdev_symlink( const char *dev, const char *dest )
+{
+    char *path;
+    NTSTATUS status = STATUS_SUCCESS;
+
+    if (!(path = get_dosdevices_path( dev ))) return STATUS_NO_MEMORY;
+
+    if (dest && dest[0])
+    {
+        unlink( path );
+        if (symlink( dest, path ) == -1) status = STATUS_ACCESS_DENIED;
+    }
+    else unlink( path );
+
+    free( path );
+    return status;
+}
+
+NTSTATUS get_volume_dos_devices( const char *mount_point, unsigned int *dosdev )
+{
+    struct stat dev_st, drive_st;
+    char *path;
+    int i;
+
+    if (stat( mount_point, &dev_st ) == -1) return STATUS_NO_SUCH_DEVICE;
+    if (!(path = get_dosdevices_path( "a:" ))) return STATUS_NO_MEMORY;
+
+    *dosdev = 0;
+    for (i = 0; i < 26; i++)
+    {
+        path[strlen(path) - 2] = 'a' + i;
+        if (stat( path, &drive_st ) != -1 && drive_st.st_rdev == dev_st.st_rdev) *dosdev |= 1 << i;
+    }
+    free( path );
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS read_volume_file( const char *volume, const char *file, void *buffer, ULONG *size )
+{
+    int ret, fd = -1;
+    char *name = malloc( strlen(volume) + strlen(file) + 2 );
+
+    sprintf( name, "%s/%s", volume, file );
+
+    if (name[0] != '/')
+    {
+        char *path = get_dosdevices_path( name );
+        if (path) fd = open( path, O_RDONLY );
+        free( path );
+    }
+    else fd = open( name, O_RDONLY );
+
+    free( name );
+    if (fd == -1) return STATUS_NO_SUCH_FILE;
+    ret = read( fd, buffer, *size );
+    close( fd );
+    if (ret == -1) return STATUS_NO_SUCH_FILE;
+    *size = ret;
+    return STATUS_SUCCESS;
+}
+
+BOOL match_unixdev( const char *device, ULONGLONG unix_dev )
+{
+    struct stat st;
+
+    return !stat( device, &st ) && st.st_rdev == unix_dev;
+}
+
+NTSTATUS detect_serial_ports( char *names, ULONG size )
+{
+    static const char *paths[] =
+    {
+#ifdef linux
+        "/dev/ttyS%u",
+        "/dev/ttyUSB%u",
+        "/dev/ttyACM%u",
+#elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+        "/dev/cuau%u",
+#elif defined(__DragonFly__)
+        "/dev/cuaa%u",
+#endif
+        NULL
+    };
+
+    detect_devices( paths, names, size );
+    return STATUS_SUCCESS;
+}
+
+NTSTATUS detect_parallel_ports( char *names, ULONG size )
+{
+    static const char *paths[] =
+    {
+#ifdef linux
+        "/dev/lp%u",
+#endif
+        NULL
+    };
+
+    detect_devices( paths, names, size );
+    return STATUS_SUCCESS;
+}

dlls/mountmgr.sys/unixlib.h

+/*
+ * MountMgr Unix interface definitions
+ *
+ * Copyright 2021 Alexandre Julliard
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#include "mountmgr.h"
+
+extern NTSTATUS add_drive( const char *device, enum device_type type, int *letter ) DECLSPEC_HIDDEN;
+extern NTSTATUS get_dosdev_symlink( const char *dev, char *dest, ULONG size ) DECLSPEC_HIDDEN;
+extern NTSTATUS set_dosdev_symlink( const char *dev, const char *dest ) DECLSPEC_HIDDEN;
+extern NTSTATUS get_volume_dos_devices( const char *mount_point, unsigned int *dosdev ) DECLSPEC_HIDDEN;
+extern NTSTATUS read_volume_file( const char *volume, const char *file, void *buffer, ULONG *size ) DECLSPEC_HIDDEN;
+extern BOOL match_unixdev( const char *device, ULONGLONG unix_dev ) DECLSPEC_HIDDEN;
+extern NTSTATUS detect_serial_ports( char *names, ULONG size ) DECLSPEC_HIDDEN;
+extern NTSTATUS detect_parallel_ports( char *names, ULONG size ) DECLSPEC_HIDDEN;